Edward M. Halvajian disclosed a combination impact cushioning bumper and automatic roadway brake in his U.S. Pat. No. 3,472,332 including an upper impact cushioning bumper mechanism 20 and a lower roadway brake mechanism 22. The bumper bar 34 and the brake shoe 52 are protruded frontwardly beyond a car body to possibly increase a wind resistance for a running car and to influence its esthetic appearance especially when a streamline car is a tendency of modern design. If Halvajian device is inferentially mounted on a rear portion of a car, a rear car when colliding the Halvajian's car positioned beyond such a rear car may impact his bumper 34 to swing down the brake shoe 52 to be braked on the roadway, deteriorating the collision result.
The present inventor has found the defects of Halvajian's device and invented the present safety vehicle bumper telescopically extended and retracted.